Acta Mechanica Slovaca, 2024 (vol. 28), issue 3
Crankshaft Bearing Hydrodynamic Lubrication Study in an Internal Combustion Engine (under variable dynamic loading)
Abdelmadjid Said, Abdelhamid Bounif, Patrick Maspeyrot
Acta Mechanica Slovaca 2024, 28(3):6-17 | DOI: 10.21496/ams.2024.023 
The engine crankshaft bearing is an important component and vulnerable part of engine. Its operating condition significantly influences the dynamic performance, efficiency and overall reliability of the engine. In modern engine design, the main objective is to improve power output while minimizing friction losses and reducing fuel consumption. This present work concerns the study of the behavior in dynamic mode of the big-end and small-end bearings of connecting rod in internal combustion engine, taking into account the rupture and reformation of the fluid film in the contact region in the inactive cavitation zone. The most important operating parameters...
Laws of Particle Entrainment from Fluidized Bed Apparatuses
Mykola Yukhymenko, Ruslan Ostroha, Denys Ostroha, Yakov Mikhajlovskiy
Acta Mechanica Slovaca 2024, 28(3):18-24 | DOI: 10.21496/ams.2024.024
The article presents the results of experimental studies of the process of entrainment of particles of fine fractions from the fluidized bed of polydisperse mixture of granular superphosphate. A review of the main analytical dependencies for determining the amount of entrainment from the fluidized bed is presented. The results of experimental studies of the entrainment process from the fluidized bed of small particles with a size less than 1 mm and large particles with a size more than 1 mm in the interval of gas flow velocities 0.5 - 5.0 m/s are given. The results of calculating the value of fine fraction entrainment from the fluidized bed of superphosphate...
Theoretical and Numerical Study on the Dynamic Behaviour of a Rotor with a Conical Steel Shaft
Rachid Zahi, Habib Achache
Acta Mechanica Slovaca 2024, 28(3):26-34 | DOI: 10.21496/ams.2024.012
This work proposes a theoretical and numerical study on the behaviour of the tapered rotor. The characteristics of the elements of the rotor are determined; it is to evaluate the expressions of the kinetic and potential energies as well as the virtual work corresponding to the basic elements disk, shaft, bearing for the two conical models by applying the method of the finite elements. Numerical simulation allows us to observe and determine modal analysis and natural values.
Specific Aspects of Roughness Measurement
Katarína Paµová, Tatiana Kelemenová
Acta Mechanica Slovaca 2024, 28(3):36-40 | DOI: 10.21496/ams.2024.028
The article deals with problems in determining the surface roughness of parts. The arithmetic mean height of the roughness Ra is mainly monitored. This quantity is most often used when defining the required surface quality of components. Assessment of surface roughness is important in the production of parts, their assembly and their use. This article solves some problems in the process of determining this quantity.
Real-Time Location Systems Across the Industries - Literature Review and Case Studies
Laura Lachvajderová, Milan Fiµo
Acta Mechanica Slovaca 2024, 28(3):42-48 | DOI: 10.21496/ams.2024.017
Real-Time Location Systems (RTLS) are pivotal in enabling the instantaneous tracking and monitoring of objects, contextualized within their immediate environment and time frame. The current industry landscape boasts a plethora of technologies and services, showcasing RTLS's expansive potential in the manufacturing, healthcare, and logistics sectors. This article endeavours to elucidate a holistic understanding of RTLS's technical proficiencies while transcending the confines of a myopic view limited to isolated solutions. It posits that RTLS-based infrastructures can be methodically engineered utilizing this technology, fostering advancements in industrial...
Optimization Study about a Hybrid Energy System (solar PV and wind) to Supply a Habitat Located in an Isolated Area in Algeria
Maamar Mouheb, Ahmed Fellah, Mohamed Amine Khorchef, Bendaoued Bencherki
Acta Mechanica Slovaca 2024, 28(3):50-59 | DOI: 10.21496/ams.2024.011
Generation of energy from renewable resources is mainly implemented to supply to remote rural areas. In this context, we attempted to exploit the renewable energy (especially solar and wind power) that characterizes a remote and isolated site in Algeria, which also benefits from motivating tourist characteristics, our aim is to develop the site through supplying habitats with clean and free energy and reducing greenhouse gas emissions. For this purpose, we suggest the installation of a hybrid energy system (PV, wind and diesel), and we will do an optimization study about the feasibility and ability of the proposed system to meet the energy needs without...
Application of Data-mining Methods in the Assessment of Excessive Vibrations: Decision Trees, Basket-market Analysis
Miriama Pinosova, Miriam Andrejiova
Acta Mechanica Slovaca 2024, 28(3):60-73 | DOI: 10.21496/ams.2025.002
The article examines the issue of assessing the impact of above-limit vibrations on the health of employees in handling and dispatch warehouses (timber yards). The results are based on the arithmetic mean of multiple measurements of both hands of the chainsaw operator or the hands/whole body of the machinist, while taking care to maintain consistency. The measurement locations, measurement duration and selection of samples were chosen so that the result represented and described the employee's personal exposure. The main objective was to identify the relationship between the working activity of the studied forest administration employees, exposure...
Characterization of Nanostructured Magnetic alloy Based on Fe- Nd-Gd-B Produced by Mechanical Synthesis
Rachid Boughedaoui, Habib Achache, Abdennour El Mohri, Rachid Zahi, Mohamed Azzaz
Acta Mechanica Slovaca 2024, 28(3):74-83 | DOI: 10.21496/ams.2024.025
This paper examines the effect of Nd substitution by Gd on the exchange coupling in the Nd₂Fe₁₄B nanocomposite. The structural, microstructural, and magnetic properties of Fe76 Nd(16-X) GdXB8 alloy (X = 0, 2, 4, 8, and 16) were investigated. Nanocrystalline alloy samples Fe76 Nd(16-X) GdXB8 (in atomic percentages) were prepared from pure elemental powders by mechano-synthesis. The obtained materials were characterized by X-ray diffraction (XRD), which helped track the dissolution of neodymium and gadolinium in the iron matrix. The maximum crystallite size obtained was 6.5 nm with a microstrain of 1.49% for our powders. Magnetic...